Persistent Non-Duchenne Smile After Facelift Surgery: An Underrecognized Functional Complication

Introduction: Aesthetic procedures have the potential to disrupt the coordination of normal smile biomechanics. Preservation of oral commissure excursion with diminished periocular recruitment is described as a non-Duchenne smile. We conduct this targeted narrative review examining the available literature and investigate anatomically plausible mechanisms underlying the persistent non-Duchenne smile associated with facelift surgery. Materials and Methods: A literature search of PubMed and EMBASE was performed from inception through December 2025 using terms related to smile anatomy, facial nerve branch anatomy, facelift techniques, and postoperative animation outcomes. Results: Recent cadaveric studies demonstrate variability in nerve supply and structural continuity between the orbicularis oculi and the zygomaticus complex. Based on these anatomical studies, we propose 2 mechanisms by which a persistent non-Duchenne smile may occur after facelift surgery: partial injury to temporal or zygomatic facial nerve branches, and structural dissociation of the zygomatico-orbicular unit. Discussion: Although not a recognized standalone complication, the available evidence supports a plausible anatomical and functional basis for postoperative smile change. Preoperative dynamic documentation and preservation of orbito-zygomatic continuity are important for assessment and prevention. Conclusion: This review presents a clinically relevant anatomical insight that may help improve both recognition and prevention of the persistent non-Duchenne smile associated with facelift surgery.